Adjustable tap holder



E. DICK ADJUSTABLE TAP HOLDER Jan. 13, 1953 Filed May 12, 1950 IN VEN TOR.

ERNEST L. DICK ATTORNEY.

Patented Jan. 13, 1953 UNITED STATES PATENT F F 1 CE 4 Claims.

This invention relates to an improvement in tool holders for turret types of lathes and similar machines. In machines of this kind it has been the practice to mount the tool on the turret and the machine will then move the work to engagement with the tool, or the tool to engagement with the work. It has been dimcult to mount the tool in exact alignment with the work, and the movements of the machine do not always coincide with the exact movement required by the tool during its period of operation; this is true particularly when the tool is a thread or tap. This improved tool holder is designed to hold the tool and compensate for or overcome the above mentioned diiiiculties.

Now referring to the accompanying drawings in which similar numerals of reference designate the same parts throughout the several figures of the drawings:

Fig. l is a combination top plan and sectional view of the tool holder device, the view being shown in its contracted position.

Fig. 2 is a combination top plan and sectional view of the tool holder device, the device being shown in its extended position. Y

Fig. 3 is a front view of the tool holder device, the view being as seen from the line III-III in Fig. 2, and looking in the direction of the arrows.

Fig. 4 is a combination top plan and sectional view of a modified form of the tool holder device.

Fig. 5 is a cross sectional view of the modified form of the tool holder device, the view being as seen from the line V-V in Fig. 4 and looking in the direction of the arrows.

. In the drawings the tool holder device is shown as being a substantially elliptical base element II that has a rearwardly extending tubular portion I I integrally formed thereon and positioned in the center thereof.

The device is provided with a second substantially elliptical shaped plate I2 having the same size and proportions of the base plate It and is adapted to fit thereagainst. The plate I2 has a rearwardly extending tubular portion I3 that is integrally formed thereonand is'positioned at the center thereof. The outside diameter of the tube I3 is considerably less than the inside diameter of the tubular element II and is therefore loosely and movably positioned within the tube I I. The plate I3 is also provided with a forwardly extending sleeve or cup-like element I4 that is integrally formed thereon and is in axial alignment with the tubular element I3. The inside of the sleeve I4 is provided with inwardly and longitudinally extending splines I 5.

= Slidable longitudinally within the sleeve. It is positioned a chuck block I6 that is provided with I longitudinally disposed grooves I! in which the splines I5 are slidably received for the purpose of preventing revolving movement of the chuck block I6 in the sleeve I4 The chuck black It is provided with a rearwardlyextending pin I8 that is in axial alignment with the chuck block It and is integrally formed thereon.

A helical compression spring I9 is positioned around the rear end of the pin l8 and is retained thereon by means of a screw that is threaded into the rear end of the pin I8 and the head 20 of the screw overlaps the rear end of the spring I9 to retain the spring on the rear end of the pin III. The forward end of the spring I9 rests on an annular shoulder 2| that is formed in the inner central portion of the tube. I3. The spring I9 serves to yieldably hold the chuck block and parts carried thereby in their retracted position in the sleeve Id. The chuck block It has an axially positioned bore 22 in the front end thereof in which isslidably received and. positioned a pair of hollow half round chuck jaws 23 and 2 3 between which is received and held the tool shank 25, the tool shown is a thread tap 25a, and as set screw 26 is threaded through the chuck block I 6 to engage the chuck jaw 23 and press or move it toward the chuck jaw 2 so as to rigidly bind and hold the tool shank 25 between the two chuck jaws 23 and 24. The sleeve It has a slot 27 therein that is open to the front of the sleeve I6 and extends rearwardly therefrom to receive the set screw 26 and permit slidable longitudinal movements of theset screw 26 in the slot 21 as will later be described The plate I2 has large holes such as shown at 28in each end thereof and screws 29 and 36 are passed, one through each hole '28 and are threaded into the base plate I 0 so that the heads 29a and 30a of the screws .29 and-3U will bear against the plate to rigidly bind and hold the plate I2 against and on the plate It in adjusted positions as will later be described.

The device may be prepared for use by first placing the tubular element II in a hole or slot in a turret head, not shown, and positioning the device therein as in a selected position and rigidly fixing the tool holder therein by means of a set screw, not shown, in the manner that such tools are usually set, or if desired the tubular element I I could be fixed in the chuck or tail stock .of a lathe in the same manner any work would be placed therein. This having beendone the shank 25 oi a desired tool such as a thread tap 25a is inserted betweenthe chuck jaws 23 and 2d and thesetscrew 26 screwed .down to tighten and rigidly hold the tool shank zibetween the chuck Jaws 23 and 24. This having been done the screws or bolts 29 and 30 may be turned to loosen the plate I against the plate Ill whereupon theplate I2 and the elements carried thereby may be moved in a plane transverse the axis of the tool 25a'to move and position the tool 25a in exact alignment with the work the tool is to act on. V I

The tool holder and tool having thus been prepared for usethe tool25a and the work, not shownymay be brough't'into engagement with each other for the purpose of threading the inner face of a hole in the work. In this operation the tool or the work may not be moved toward each other as fast as is required by the pitch of the threads being cut, therefore this discrepency is compensated for by the pull of the tool or the work toward each other, whereupon the chuck block l6 and tool 25a carried thereby will be pulled forward against the resisting upressure'o'f the spring [9. Similar movements in reverse .order will be effected when the turning movement of either the work or tool is reversed to withdraw the tool from the work.

In Figures 4 and 5 is shown a modified form of the device in wh'ich tug-Juggernau a is substituted for the .base plate In in Figures 1 an a t e t u arl i eiit H is nts e form d n and is in axial a i nment with "the cup lea. Within the tube II are all the parts 13, I8, 19 and 20 and 2! precisely the same as described in Figures 1 and 2, also the sleeve i4, chuck block 16, chuck jaws Hand 24, set screw 2.6 and slot 2'! are all the same as described in Figures 1, 2 and 3 except that the sleeve M provided with an outwardly extending annular flange 31 therearound that is integrally formed thereon at the rear or base thereof and is adapted'to rest on and against the inside faoefo'f the bottomof the cup um." Thefiange fl is provided with an outwardly 'extendingleg 32 that is'loosely'pcsitioned in a hole 33 in the Side Wall of the cup Hie adjacent the bottom thereof. The flange 3] is considerably less in diameter than the inside diameter of the cup illa, therefore the sleeve 14 can be moved to numerous positions and the axis thereof will always remain in parallelism with that of the tubular element II. A sleeve 34 having holes 340. in the center edge thereof-that is threaded within theinner face of the wall of the cup element 10a to engage and bear against the flange 3| whereby the sleeve I; may be moved t le ted pcr it ons r 9 P95i1 9 h th am as described for Figures l, 2 and 3. This adjustment having been made the sleeve 34 may be tightly screwed against the flange 3| by means of a spanner wrench that may be placed in the holes 34a to hold the sleeve I4 and the parts it carries in their adjusted position. The leg 32 will prevent the sleeve 34 from'turning in the cup Illa under the urge ofthe tool in the processor the tool 25 doingits work.

While the device as shown and described is probably the preferred forms of the device it is to be understood that such modifications of the device'may' be'employe'd as he within'the scope of the appended claims without departing from the spirit and intention 'o'f'theinvention. Now having fully shown an described m invention, what'Iclaimis:

1. In a tool holder device of the kind described; a tool chuck and means for rigidly holding a tool in the chuck, a chuck holder and carriage therefor, said chuck 'b'eing yieldably movable longitudinally and'non-re'volvable insaid chuck holder; and means for adjusting and rigidly-holding the said chuckholder' in adjusted parallel positions about the :center longitudinal axis of the said chuck holder carriage, and means on said carriage for the mounting of the carriage on a machine.

2. In a tool holder device vof the kind described and as defined in claim 1 said chuck being movable outwardly from the said'chuck holder by the pull of the tool held therein, and spring means 4 for retracting the chuck as the pull of the tool is released.

3. In a tool holder of the kind described and as defined in claim 1; said carriage having a face plate and a tubular support extending rearwardly tubular element to permit radial adjustment movements of the second said tubular element within the first said tubular element, said chuck holdercup being ren ageable againstthe face plate of the said carriage to maintain parallelism between the center longitudinal axes of the first and second said tubular elements, said chuck having a rea'rwardly extending stem, slidably passing through the said cup and being slidably receivable in the second said tubular element, a spring positioned around the said stem of the chuck, one

end of said spring resting on and being supported by a shoulder formed within the second said tubular element, and means carried by the rear end of said chuck stem and engaging the other end of said spring for'the yieldable retracting movement ofsaidch'uck. w

4(In a tool holder device of the kind described; a tool chuck and means for rigidly holding a tool in the chuck, a chuck holder and carriage there for; said chuck being yieldably movable longitudinally and non-revolvable in said chuck holder, and means for adjusting and rigidly holding the said chuck holder in adjusted parallel positions about the center longitudinal axis of the'said chuck holder carriage, and means on said carriage for the mounting of the carriage on a machine, aid a na e a i g an annu ar e pla e and a forwardly extending annular flange portionintegrally formed thereon and having a passage through said flange, said chuck holder having an outwardly extending flange therearound and rest.- ing against thelsaid faceplate and having means thereon extending through the passage in the first said flange .to prevent relative rotation between the said chuck holder and the said carriage, the outside diameter of the chuck holder flange being'iconsiderably less than the inside diameter of the carriageflange, a lock ring, said lock ring being threaded into .the said ewe-g9 flange and engageable Iwithithe flange ofthe chuck holder the inside diameterbf s'aid ring being considerably greater than the outside diam; eter of the chuck holder' and means for-turning said ring to ms and hold the chuck holder in radially adjustediiiositioris relative to "theifac e m te of the c rri ge.

R ES L- DI K I REFERENCES crrnp The following references are of record in the file of this patent:'

IT TATE$ PATE S Number Name Date 1,369,491 Straehle Feb; 22,192! 1,377,663 Brownet al. "gt/ra 10,1921 1,702,810 Buhr Feb. 19; 1929 2,524,852 Straun ioct. 1'0, i959 FOREIGN Pn'raurs Em er QQ t y Dat l9 5 Great Britain June 7, 1917 

